<template>
  <div class="xtx-dialog" :class="{fade}" v-show="visible">
    <div class="wrapper" :class="{fade}">
      <!--头部-->
      <div class="header">
        <h3>{{ title }}</h3>
        <a href="JavaScript:;" class="iconfont icon-close-new" @click="closeDialog()"></a>
      </div>
      <!--对话框内容-->
      <div class="body">
        <slot/>
      </div>
      <!--底部-->
      <div class="footer">
        <slot name="footer"/>
      </div>
    </div>
  </div>
</template>
<script>
// vue3.0 v-model:visible语法糖，拆解（:visible + @update:visible）
// vue2.0 visible.sync语法糖，拆解（:visible + @update:visible）
import { ref, watch } from 'vue'

export default {
  name: 'XtxDialog',
  props: {
    title: {
      type: String,
      default: ''
    },
    visible: {
      type: Boolean,
      default: false
    }
  },
  setup (props, { emit }) {
    const fade = ref(true)
    // 改造动画执行时机
    // visible的值为true时打开
    watch(() => props.visible, (newVal) => {
      // 结构和样式同时加上无过度效果，需要些延时。
      setTimeout(() => {
        fade.value = newVal
      }, 0)
    }, { immediate: true })

    // 自己关闭对话框，修改父组件数据状态
    const closeDialog = () => {
      emit('update:visible', false)
    }
    return { fade, closeDialog }
  }
}
</script>
<style scoped lang="less">
.xtx-dialog {
  position: fixed;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  z-index: 8887;
  background: rgba(0, 0, 0, 0);

  &.fade {
    transition: all 0.4s;
    background: rgba(0, 0, 0, .5);
  }

  .wrapper {
    width: 600px;
    background: #fff;
    border-radius: 4px;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -60%);
    opacity: 0;

    &.fade {
      transition: all 0.4s;
      transform: translate(-50%, -50%);
      opacity: 1;
    }

    .body {
      padding: 20px 40px;
      font-size: 16px;
      max-height: 500px;
      overflow-y: auto;

      .icon-warning {
        color: @priceColor;
        margin-right: 3px;
        font-size: 16px;
      }
    }

    .footer {
      text-align: center;
      padding: 10px 0 30px 0;
    }

    .header {
      position: relative;
      height: 70px;
      line-height: 70px;
      padding: 0 20px;
      border-bottom: 1px solid #f5f5f5;

      h3 {
        font-weight: normal;
        font-size: 18px;
      }

      a {
        position: absolute;
        right: 25px;
        top: 25px;
        font-size: 24px;
        width: 20px;
        height: 20px;
        line-height: 20px;
        text-align: center;
        color: #999;

        &:hover {
          color: #666;
        }
      }
    }
  }
}
</style>
